English: Many different species of phytoplankton colour the ocean’s surface. Very common in the South Atlantic bloom, coccolithophores are probably responsible for the milky blue colour in this image. Sunlight reflecting off the surface of the water is turning the water’s surface silver in the lower left corner. Many environmental factors come together to make the South Atlantic ideal for this large annual bloom of millions of micro-organisms. First, the chilly Malvinas Current, a north-flowing branch of the Antarctic Circumpolar Current, flows north along the edge of the South American continental shelf. The current brings cool, nutrient rich waters north. Water also rises to the surface along the edge of the continental shelf, bringing additional iron to sunlit waters. Finally, the Rio de la Plata deposits nitrogen and iron-laden sediment into the ocean just north of the area shown in the image. Though this image covers hundreds of kilometres, it shows only a portion of the entire bloom.